<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<style>
    body{
        width: 1200px;
    }
    .banner{
        width: 800px;
        height: 1200px;
        background-color: rebeccapurple;
        margin: 0 auto;
    }
    .logo{
        width: 30px;
        height: 50px;
        background-color: plum;
        position: fixed;
        left: 600px;
        top: 300px;
        margin-left: 400px;
        /*margin-top: 400px;*/
    }
</style>
<body>
<div class="banner">

</div>

<div class="logo">

</div>
</body>
</html>